1. Field of the Invention
The present invention relates to an information input apparatus to input information to an information processing system and, more particularly, to an information input apparatus to input information to an information processing system by touching, e.g., a finger or the like, an input surface.
2. Related Background Art
What is called a touch panel apparatus is known as a kind of information input apparatus. This touch panel apparatus is assembled in a computer system or an information processing system using a computer and is used by overlaying a transparent input section onto a display surface of a display device in the information processing system. An operator can input information by touching indicating means, such as a pen, finger or the like, onto the input surface of the input section of the touch panel apparatus while looking at the content displayed on the screen of the display device or the like through the transparent input section of the touch panel apparatus. In general, a power source is supplied to the touch panel apparatus from, for instance, the main unit of the information processing system and the turn-on/off of the power source cannot be performed by the touch panel apparatus itself.
In the touch panel apparatus, since the information is input by touching a pen, finger or the like onto the input surface, dirt is deposited onto the input surface by the touch. When this dirt is cleaned, if the cleaning is performed after the turn-on of the power source of the information input apparatus, that is, in a state in which information can be input, the input surface is touched at random by the cleaning operation, so that the input is erroneously executed and a malfunction of the apparatus occurs. Therefore, when cleaning, it is necessary to turn off the power source of the touch panel apparatus by turning off the power source of the information processing system main unit.
However, since the information stored in a memory or the like is erased by the turn-off of the power source of the information processing system main unit, it is necessary to perform complicated operations such that the stored information is previously saved into a non-volatile memory or the like. On the other hand, in the case where the power source of the apparatus cannot be turned off because the information processing system is operated for twenty-four hours in a day, there is a problem such that the input surface cannot be cleaned or the like.